Evaluation of the thermal stability and digestibility of heterologously produced banana lectin

The thermal stability of recombinant mannose-specific banana lectin (rBanLec), as well as its stability under conditions of simulated gastro-intestinal fluid (SGF), was investigated. rBanLec was heterologously produced in Escherichia coli, Molecular mass of rBanLec, assessed by ESI-TOF mass spectrometry, was 15972.2 Da. Thermodynamic parameters for rBanLec denaturation, obtained by differential scanning calorimetry (DSC), revealed a transition maximum temperature (T(m)) of 60.8 degrees C, calorimetric enthalpy (H(cal)) of 136.17 kcal/mol and van't Hoff enthalpy (H(VH)) of 50.27 kcal/mol. rBanLec was stable following an incubation for 2 h in SGF, and then for I h, in the simulated intestinal fluid (SIF). Intact primary structure, biological and immunological reactivity of rBanLec were all preserved following treatment under SGF and SIF conditions. In conclusion, rBanLec is a good candidate for the novel bioadhesive lectin-based drug delivery systems to the gastro-intestinal tract (GIT). (C) 2009 Elsevier Ltd. All rights reserved